It is known that after an injury to a central or a peripheral nerve, nerve regeneration depends on the elongation or regrowth of axons destroyed at the site of injury. Axon elongation or regrowth, however, is hindered by the structural and metabolic changes that occur at the site of the nerve injury. For instance, when a nerve is injured, nerve cells and blood vessels are destroyed with the release of serum, proteins, plasma fluid, cells, growth factors, and crushed tissue. In turn, the body recruits macrophage to clean the dead cell and blood vessel debris and clean the environment. In addition, macrophage release cytokines and other growth promoting factors to stimulate tissue repair.
In a long lasting injury, the tissue repair process progesses to a chronic stage where the body recruits fibroblasts to the site of the nerve injury. Fibroblasts release growth factors that help to recruit additional fibroblast to facilitate the repair process. This cycle leads to the buildup or overgrowth of exuberant fibrous tissue at the site of the nerve injury. Exuberant fibrous tissue overgrowth, however, prevents the nerves from interconnecting and regenerating, and hinders the axon and neuronal cells from proliferating. Consequently, a need exists for a device and method that prevents exuberant tissue overgrowth from impeding or interfering with the nerve regeneration or regrowth process.
In addition to the problems caused by exuberant tissue overgrowth, the axons have no guidance as they elongate during the repair process. Consequently, the axons elongate into a tangled web of unorganized axons. A need therefore exists for a device and method that provides axons guidance as they elongate during the repair process. The present invention overcomes the known problems encountered during the nerve regeneration process.